Let \( X \) follows binomial distribution with parameters \( p \) and \( n \). The probability mass function of \( X \) is
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a. \( \quad p_{X}(k)=\binom{n}{k} p^{k}(1+p)^{n-k}, \quad k=0,1, \ldots, n \).
b. \( \quad p_{X}(k)=\binom{n}{k} p^{k}(1+p)^{n+k}, \quad k=0,1, \ldots, n \).
c. \( \quad p_{X}(k)=\binom{n}{k} p^{k}(1-p)^{n+k}, \quad k=0,1, \ldots, n \).
d. \( \quad p_{X}(k)=\binom{n}{k} p^{k}(1-p)^{n-k}, \quad k=0,1, \ldots, n \).
